Little information is currently available on the structural relationships and innervation of the mammalian urinary bladder, and particularly on that of man. This deficit causes problems with the treatment of patients and the development of therapeutic measures for bladded dysfunctions. The lac of animal data complicates experimental research, including drug research, since there is no animal model for the human bladder. Therefore, the pattern and character of the innervation to and the structural organization of the human bladder and that animal tissue which is most comparable, the human and dog bladders, including tissue from each of the three regions, will be examined in a multifaceted morphological study, supplemented by pharmacological data from the coinvestigator. Specific aims are: 1) to examine the structure of the bladder with detailed morphological methods, including fine structural morphometry using serial section reconstruction analysis, 2) to assess and evaluate the innervation of the bladder using several histochemical techniques, including the imunocytochemical localization of several neuropeptides, and 3) to correlate the results of these morphological studies with the data from In Vivo muscle bath and receptor bindsing assays being done by the coinvestigator. The light microscopic methods include glyoxylic acid histofluorescence, acetyl-cholinesterase localization, and immunocytochemistry of several neuropeptides. The ultrastructural methods include routine glutaraldehyde fixation, special glutaraldehyde dichromate fixation for specific localization of norepinephrine, and analysis of positive reaction sites from the immunocytochemical studies using the PAP method. Data from these experiments will provide: 1) basic information on the human bladder, which should be of assistance fo clinicians in formulating surgical and pharmaceutical therapeutics, and 2) further basic data on the bladder of the dog, the organ that seems most representative of the human tissue, a necessary early step in the search for an appropriate animal model.